1. Field of the Invention
The present invention relates to a method of producing seaweed paste of Undaria pinnatifida, sea tangles, Nemacystus decipiens and the like, and seaweed paste obtained by such a method.
2. Description of the Related Art
It is said that the amount of production of seaweeds in the world is 20,000,000 t/year, and that 750,000 t/year of seaweeds are used in Japan. However, it is said that a much greater amount of seaweeds are not effectively used and disposed as industrial wastes.
In U.S.A., it is believed that seaweeds are effective as substitutes for starch and fats, and studies on seaweeds have been actively carried out. In Japan, people have started to recognize seaweeds as good materials for health. In particular, sticky components in seaweeds are noted in all foods, and thus they reached to find various functions of seaweeds, for example, (1) action of improving bowel movement, (2) anticoagulant action, (3) anticancer action, (4) action of reducing cholesterol, (5) action of decreasing blood pressure, (6) antiviral action, (7) antiallergic action and (8) therapeutic effect on indefinite complaint.
However, seaweeds are not utilized extensively for their low processing suitability.
Conventionally, paste of seaweeds refined to a unit such that the seaweeds can be entirely absorbed in the body has been developed. However, seaweed particles in such a paste are rough and uneven, and such a paste does not have sufficient processing suitability.
Japanese Laid-Open Patent Publication No. 10-155462 (Patent Document 1) discloses the following method of producing noodle-shaped solidified food of Undaria pinnatifida. 
Dried Undaria pinnatifida which has swelled by addition of water is placed and ground in a vacuum-heating/cooling kettle with a high-speed cutter. After adjusting the pH level to pH 5-6 with an acidulant, 0.8-1% by weight of cellulase is added to the Undaria pinnatifida, and the mixture is heated and stirred for 30 minutes to 1 hour at 40-50° C. 0.4-0.6% by weight sodium citrate is added and the mixture is heated and stirred for 1-2 hours at 70-80° C. A vacuum pump is simultaneously run, and the interior of the kettle is vacuumed to 0.5 atmosphere or less and is de-aerated. Finally, a cooling machine is run to cool the solution of Undaria pinnatifida to a normal temperature.
The resulting solution is discharged into 3-5% calcium lactate aqueous solution, thereby obtaining a noodle-shaped solidified food of Undaria pinnatifida. 
However, as the production method as described above requires heat treatment of Undaria pinnatifida for 1-2 hours at 70-80° C., the Undaria pinnatifida experiences significant discoloration and loss of aromatic component, thereby deteriorating quality of the resulting food. Furthermore, relatively long time of treatment results in low productivity and high production costs of the solidified food.    [Patent Document 1] Japanese Laid-Open Patent Publication No. 10-155462